Electric iron



April 7, 1959 F. c. SCHWANEKE 2,830,530

ELECTRIC IRON 4 Sheets-Sheet 1 Filed April 27, 1954 INVENTOR. [red a 50W April 7, 1959 F. c. SCIHWANEKE ELECTRIC IRON INVENTOR.

a]? BY W i ma 4 Sheets-Sheet 2 m d h Flled Aprll 27, 1954 F. C. SCHWANEKE ELECTRIC IRON 4 Sheets-Sheet 3 I Filed April 27, 1954 6 ii W A7/// 223 y MWEESE \ww x 7 i 7 mwm p 7 w J a W M% 20 INVENTOR.

fi ed C Stiwazzezfa I April 7, 1959 F. c. SCHWANEKE ELECTRIC IRON 4 Sheets Sheet 4 Filed April 27, 1954 5 r r? i ww R a NM United States Patent ELECTRIC IRON Fred C. Schwaneke, Chicago, Ill., assignor to Dormeyer Corporation, Chicago, 111., a corporation of Illinois Application April 27, 1954, Serial No. 425,814

Claims. (CI. 38-77) The present invention relates to electrically powered irons and, more particularly, to irons which are thermostatically controlled and perform their function either dry or with steam discharged through openings in their sole plate.

With the advent of fabrics which are made of synthetic materials that should be ironed at temperatures as low as the boiling point of water, conventional steam irons are unable to supply steam and still stay at the desired temperature. At the necessary low setting required for fabrics in the lower range, either the water spots without becoming steam or the sole plate is either too hot or too cold, depending on which way the manufacturer biases the thermostat to reach for low operation. Others either do not specify steam at low temperatures or indicate that fabrics should not be ironed with steam at low temperatures.

Rayon preferably is ironed at 225 F., acetates at or below 225.

The present invention contemplates the ironing of fabrics at temperatures as low as 200 R, if desired (thermostat setting) with or without steam and without water spotting the fabrics.

It is common knowledge that water has a boiling point of approximately 212 F. at atmospheric pressure and at this temperature the water in its liquid phase has a heat content of 180 B.t.u. per pound of which 142 B.t.u. per pound is added above room temperature. The latent heat of vaporization of water is approximately 970 B.t.u. per pound making a total heat content of 1150 B.t.u. to convert Water to steam at 212 of which 1112 B.t.u. has to be added by the iron. This is not the minimum steam work load carried by the iron up to 212 not including loss of heat by radiation during the process.

Translating this B.t.u. heat load into electrical energy (34 B.t.u. per watt), it represents approximately 328 watts, and translating the pound of water into drops,

7680 drops per pound, it mathematically appears that based upon a preferred minimum dispensing of 40 drops per minute in a steam iron, approximately 104 watts are required each hour of operation to supply the latent heat of vaporization. This, added to the watt hours consumed by a dry iron in carrying a reasonable work load, which amounts to approximately 105 watt hours, makes the total work load on the iron approximately 209 watt hours. Roughly speaking, the steam load is /z of the total load at 212 F. for 40 drops of water per minute.

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with /2 or less of the heat developed expended over a Some irons intermittently use water at as high a rate as six ounces in a quarter hour in which case the B.t.u. steam load would be rated as 492 watt hours or approximately four times the dry iron wattage.

Where the electrical heater is embedded in intimate heat exchange contact with the sole plate,-th'e heat re- 1.

quired for generating steam must be expended in a very restricted area and to reach this area must pass through wide area, the limited area chills down and fails to supply sufiicient latent heat of vaporization and water spots occur. This difficulty is magnified the greater the number of drops dispensed. Sixty drops per minute would further chill the limited area, and although the thermostat would provide more heat, the proportion of heat expended would be further unbalanced.

Heretofore, conventional endeavors have been to lengthen the steam conducting passageways to labyrinth proportions entailing costs and still not solving the problem below a thermostat setting of 250 without danger of overshoot in a high Wattage iron or spotting.

In the present invention, the member containing the embedded heater is separate from the sole plate member. The two are assembled to have limited contacting areas so that heat exchange between the two is controlled. The thermostat is located in heat exchange contact with the sole plate while the chamber for the flash vaporization of the water is associated with the member containing the heater. Thus a surplus of heat not directly or quickly affecting the thermostat is avalable for vaporization before it could enter the metal stock of the sole plate, yet danger of overheating the sole plate is greatly minimized because the heat input into the sole plate is controlled. Rapid heat supply to the sole plate is cushioned or eliminated, both by controlled heat transfer and by steam contacting and tempering the sole plate temperature at lower settings without chilling it as it passes from the flash vaporization chamber through holes in the sole plate.

Another object of the invention is to provide an improved domestic steam iron which will operate to iron with steam in full expected quantity throughout a range starting as low as 200 without water spotting the fabrics.

The invention is further characterized by the midportion of an embedded heater (where the highest heat per lineal heater unit is developed) being located primarily in heat exchange relationship with a steam generating chamber which requires at least /3 of the heat load during steam ironing, and secondarily, in restricted heat exchange with the sole plate of the iron through the metal body in which the chamber is an integral part.

It is a further object of the invention to reduce heat exchange between the generated steam and the sole plate yet enable the steam, if heated above 212, to supply substantial amounts of heat to the sole plate, such eX- change supplementing the metal-conducted heat that is controlled by limited heat exchange metal contact.

The invention is also characterized by a performance wherein under an expected load of steam ironing at approximately 212 (sole plate temperature) the heat exchange rate from a conventional high wattage heater, as high as 1100 watts, to the steam chamber is enough to supply 350 B.t.u. or more per hour for water vaporization when the work load upon the iron totals 700 B.t.u. per hour or approximately 200 watt hours. (The advantages which dictate the desirability of a high wattage heater is quick warm-up and quick recovery.)

A further object of the invention is to provide heat exchange between a source of heat and the sole plate of an iron partially by radiation when the iron is operating without steam.

A further object of the invention is to provide a steam chamber in which calcium can be deposited to serve as a quick water-absorbent coating that prevents bounce and sputter of the water drops when they first contact the hot surface, thereby accomplishing quick vaporization.

A further object of the invention is to supply adequate heat to vaporize mineral oil for conveyance by steam to revitalize fabrics being ironed or pressed, the flash or 3 vaporization point of such oils being approximately 325 and the latent heat of vaporization approximately 125 B.t.u. at that temperature.

A further object of the invention is to provide an improved control for regulating the flow of water to the steam chamber.

A further object of the invention is to provide an improved steam iron construction which is easy to service and maintain and readily understood and operated by persons not skilled mechanically.

A further object of the invention is to provide an improved sole plate and steam generating chamber which is simple to manufacture and easy to assemble and keep clean.

These being among the objects of the invention, other and further objects will be apparent .from the drawings and the description relating thereto.

In the drawings:

Fig. 1 is a vertical sectional view taken longitudinally through a steam iron embodying the invention;

Fig. 2 is a plan view of the bottom portion of the steam iron shown in Fig. 1;

Fig. 3 is an enlarged segmented view partially in section taken upon the line 33 in Fig. 1;

Fig. 4 is a bottom plan view of one of the members assembled with the sole plate shown in Fig. 1;

Fig. 5 is a plan view of the steam chamber with the cover plate removed;

Fig. 6 is a sectional view taken upon the line 66 in both Fig. 2 and Fig. 4; and

Fig. 7 is a section taken along the line 77 in both Fig. 2 and Fig. 4.

In general, the iron embodying the invention comprises a sole plate 10, a finishing housing 11 having a tank 12 therein, a handle 13 having a valve construction 14 at the front end, a manual heat control dial 15 below the grip 16 of the handle 13 and an extension cord 17 by which electricity is supplied to the heater components of the iron extending preferably vertically through the rear end of the handle.

More particularly, the sole plate is made up of essentially four units, the bottom member 20 of high heat conductive metal, the heater carrying member 21, also of high heat conductive metal, the cover 22 for the heater carrying member of low heat conductive metal, and the thermostat indicated generally at 23. The bottom member is preferably made of die cast aluminum of substantially uniform thickness throughout the major portion thereof, but has an upwardly-projecting flange 24 surrounding its marginal edge shaped to mate with the lower marginal edge of the finishing housing 11. Within this marginal flange 24 a channel or cavity is defined at 25 that is U-shaped in its plan view as bounded by a continuous upstanding wall 26. Leading from the cavity 25 are steam openings 27 through the bottom wall that terminate in enlargements 28 to form a part of conventional grooves 30 on the bottom of the lower member where the face is highly polished for ironing purposes. Steam is ejected through the openings 27 and along the grooves 30 when steam is being generated as more particularly described hereinafter.

The heater carrying element 21 has a lower marginal flange 31 which follows the inside contour defined by the walls 26 of the cavity 25 in snug relationship, and the lower face of the heater carrying member 21 may also be provided with a plurality of lands 32 and 33 whose lowermost faces are coplanar with the flat bottom of the cavity 25. The arrangement of the lands 32 and 33 "are more particularly shown in Fig. 4. The outermost land 32 preferably defines the overall :size of the heater catying member in ahorizontal direction, whereas the innermost flange 33 defines a path through which steam passes to reach the openings 27.

The bottom area of the land 32 and 33 defines premetal stock of the member 21 and the metal stock of the sole plate 20. Above the pathway 34, the heater 35, which is a U-shaped metal encased resistance heater of high wattage (800-1000 watts), is embedded in a boss 36 of extra thickness on element 21 which follows the heater in its shape. The heater is cast in this boss at the time the heater carrying member 21 is die cast so that intimate heat exchange contact is present throughout their interface and the ends of the heater extend outwardly as at 37 at the rear end of the element 21 where heater contacts 38 may be welded in electrical conducting relationship with the leads in the wiring system of the iron.

It will be apparent from a study of Fig. 2 with reference to the heater carrying element 21 that the heater indicated in dotted lines 35 is substantially U-shaped in construction and as more particularly shown in Fig. 5, the stock of the heater carrying element 21 on the in- 'cluded side of the curve of the heater is shaped or cored out to provide a :steam generating chamber at 39. The walls 43 of this chamber are designed to give maximum surface contact with fluid present therein and have an exit through a narrow slot 40 into a diverging passageway 41 that has a diverting island 42 therein which causes the fluid to follow many turns at which the steam is forced to come into violent contact with the walls 43 of the steam generating chamber. Beyond the island 42, two narrow converging throats 44 rejoin the two streams of fluid with violent confluence and thereafter the fluid is again separated into diverging passages 46 to pass over walls 47 and down through openings 48 to the channel 34 in the cavity 25. Reference being made to Fig. 1 in this connection, it will be noted that the bottom wall of the steam generating labyrinth as indicated at 50 is a gradually declining one to the wall 47. .It will be observed that fluid present in the steam generating chamber which is forced to flow under steam expansion is directed into violent contact many times with the walls adjacent to the heater before the fluid finally passes through the openings 48 to be conducted along the pathway 34 to the holes 27 that lead to the bottom of the sole plate. Preferably the fluid engaged area of these walls is equal to or greater than the coplanar area of the lands 32 and 33.

The cover 22 is made of a low heat conductive metal such as stainless steel and preferably covers only the steam generating chamber and labyrinth as held in place by screws 51 'in sealed relationship around the margin of the steam chamber. Directly above the steam chamber 39 the cover is provided with an upset annulus 52 on top of which rests a heat insulating washer 53 preferably made of silicone rubber so that conduction of heat is blocked at this point.

Between the two rearmost legs of the Uashaped heater and on the bottom of the lower member 2%), the thermo stat 23 is mounted with the thermal-motive element 54 thereof in heat exchange contact solely with the bottom member 20. The thermostat employed in this particular embodiment is the one shown in the Schwaneke Patent No. 2,753,419, reference to which is hereby made for a more detailed description of the parts and elements, it being sufiicient here to point out that the thermal-motive element 54 has a coefiicient of heat expansion greater than the triangular-shaped element 55 which carries the lower blade 56 of the switch so that as heat in the lower member 20 rises, the ends of the triangular element 55 are separated to cause the blade 56 to move downwardly away from the upper blade 57 to break engagement between the electrical contacts 5'8, the upper blade57 being located in adjustableposition by an adjusting pin 66 driven by the dial 15.

With the construction described thus far, it will be appreciated that the intense heat developed .by the high Wattage heater 35 is absorbed into the aluminum stock of the element 21 where the heat is first made available to the steam generating chamber 39 t and throughout the labyrinth leading therefrom, and secondarily made available to the lower member through the lands 32 and 33 and into the lower member through the controlled or limited heat exchange contact relationship existing between the area of the bottoms of the lands and the bottom of the cavity 25.

The thermostat, however, is not subjected directly to the heat present in the stock of the element 21, but is sub ject only to that heat which has been conveyed through the lands to the lower member 20. Thus if heat units developed by the heater 35 are being used to vaporize water in the chamber 39, there will be less heat units passed to the lower member through the lands 32 and 33 and as the heat in the lower member in the ironing operation is depleted through absorption by the fabrics being ironed, the temperature of the thermal-motive element 54 will fall to cause the contacts 58 to again be brought into engagement, whereupon the heater 35 will again be turned on and the first heat again made available for the generation of steam and the leftover heat for ironing.

This is contrary to conventional theories of ironing practices, and accomplishes an unusual and unexpected result in that the bottom member or ironing plate of the iron can be kept at a lower temperature than heretofore possible, yet there is more than enough thermal units available developed by the heater to generate steam. On the other hand, when there is no steam generation, the heat from the heater 35 is transferred through the lands to the sole plate 20 in a controlled relationship, making of the heater 35 because of this limited heat transfer relationship, in effect, a heater of effective wattage as low as 150 watts, which provides for a smoother performance with more heat stored in the element 21 during the off cycle of the heater 35 to be conducted and radiated into the sole plate 20 while the heater is off, yet will not permit a surge of heat in the high wattage heater 35 that would cause hot spots in the sole plate when the heater is turned on again.

The valve indicated generally by the numeral 14 is one that is assembled when the cover 11 is installed, and also serves to hold the cover 11 in place in its assembled position. From its margins, which follow the contour of the lower member 20, the cover 11 comprises a stainless steel shell 60 which arches upwardly to any desired design shape so that sufficient space is contained therein for the storage of a substantial amount of water for steam generation. The water is supported in a depending tankdefining bottom portion 12, whose marginal edges are welded to the shell as at 61 where the marginal edges r engage the finishing shell 60. Thus a tank indicated at 62 is provided above the chamber 39 and right above the chamber 39 the bottom wall of the tank 12 is depressed as at 63 to provide a low point in the tank. An opening through the depression 63 receives the threaded end 64 of a kerf-headed sleeve nut 65 whose shoulder at 66 engages the upper face of the depression 63, and as turned by a screw driver clamps the bottom portion of the depression 63 against the seal 53 and draws down upon the side walls of the tank element 12 to locate and hold the marginal edges of the finishing housing 60 against the flange 24 of the sole plate 20.

At its threaded portion 64 the sleeve nut 65 has an opening therethrough of reduced diameter as at 68 to provide a valve port above which side openings 70 are provided through the wall of the sleeve nut at the lowest possible point to permit water present in the tank 12 to reach the valve port 68.

. With the elements just described assembled as illustrated, it will be appreciated that the water permitted to enter the vaporization chamber 39 can be controlled at the valve port 68 by means of a needle valve having a tapered lower end 71 that is raised and lowered to vary adjustably the area of valve opening. Such a valve is inserted in the final assembly through an opening 73 in the top of the tank 62 where a sleeve 74 is riveted to the housing 60 as at 75 to receive a cap 76 on a top thereof.

At its front side the sleeve 74 having a shoulder thereon is provided with a threaded opening 77 which receives a threaded sleeve nut 78 therein, which also provides a tank vent opening 81. The handle 16, whose shape is apparent from the drawing, is apertured at the front end as at 82 to receive a cup washer 83 therein after the handle has been located in place. Thereupon the sleeve nut 78 is threaded into place to lock the cup washer in rigid relationship between the handle and the sleeve 74 in assembled relationship.

A plug cap 84 having spring fingers 85 thereon is then snapped into place to close the outer end of the cup Washer. Then when it becomes desirable to fill the tank with water, the iron is upended, water is poured into the cup washer 82 which drains through the main opening 81 leaving the opening through the sleeve nut 78 to bleed air from the tank as water displaces it.

The upper end of the handle is recesses as at 86 to receive a dial 87 therein secured to the upper end of the valve 14 by a set screw 90. The recess 86 has an inclined cam face 91 with an o depression indicated at 92, and the dial 87 has corresponding mating contour on the bottom thereof as at 93 with an ear 94 inclined to ride up and out of the recess 92 whenever it is desired that the valve 14 be raised. The valve 14 is urged to its normally closed position by a compression spring 95 disposed between the cap 76 at one end and a washer 96 at the other end carried by the valve stem. On top of the handle, as indicated at 97, in an indicia boss which c0- operates with the dial 87 to indicate the relative position of the valve 14 and the relative position between the tapered valve stem 71 and the valve seat 68, so that the number of drops per minute can be regulated by turning the dial 87 or the valve can be closed by turning the dial 87 until the car 94 is received in the depression 92.

The tank 12 has an opening therethrough defined by a sleeve 100 which accommodates the shaft 60 of the thermostat control, which is threaded into the thermostat housing 101 as at 102 for relative axial displacement between limits provided by a set washer 103 and a stop 104. Thus as the dial 15 controlling the thermostat is turned, the upper leaf, as already mentioned, is raised or lowered to determine the relative point at which the contacts 58 will make and break in supplying electricity to the heater 35.

The connections to the heater and the thermostat are had through the rear end of the handle, preferably in a vertical direction by the cord 17 passing down through a strain element held in place by a clip 111 within the handle cavity 112. One of the two wires in the cord is fastened to a contact bar 113 supported on an insulating block 114 whose other end is welded to one of the ends of the heater. The other end of the heater is connected as at 115 to the upper one of the contacts 58.

The other contact, in turn, is connected as at 116 to the other one of the two leads in the cord 17.

It will be noticed that the cord leads, where they are connected to the respective elements, are fastened as at binding posts with screws 117 accessible through an opening below the overhang of the finishing housing 60 and the rear end of the lower member 20, where a closure plate 118 is mounted in place by a screw 120 threaded into a bracket 121 that is secured in place by the screw 122 which holds the insulating block 114 in place. Screw 122 also holds another bracket 123 in place which receives a screw 124 that holds the rear end of the handle in place as at 125.

The assembly of the iron is readily apparent. The thermostat 23 is assembled to the bottom member 20 by conventional means such as screws 127, the heater hearing element 21 is inserted in the cavity 25 with the walls 26 therearound upset at a plurality of spaced points as at 128 to force the lands 32 and 33 into firm heat exchange engagement with the bottom of the cavity 25,, preferably with a limited amount of silicone rubber sealer disposed at their inner face to inhibit to a slight degree the heat exchange relationship between the lands and the lower member. Thereafter the stainless steel plate 22 is fastened in place by the screws 51. The electrical connections between the thermostat, the heater and the leads supported by the insulating block 114 are then completed along with the installation of the bracket 123 and bracket 121 when the screws 122 are fastened in place.

The cover 60 without the handle 16 and without the cap 76 in place is then brought into proper position to rest upon the flanges 24 at the marginal edges thereof. The sleeve nut 65 is then inserted through the opening 73 and tightened in place with the silicone washer 53 under compression to form a heat block at that point. The sleeve washer 65. is, tightened firmly in place to hold theshell under stress tension rigidly in place. Thereafter the valve stem 14 is lowered in place with the spring @5, washer 96, and cap 76 installed thereon, and the handle 16 lowered in place to receive the threaded nut 78. which secures it at the front end and the screw 124 which secures it at the rear end.

With the handle installation the leads of the cord 17 are arranged where they are accessible through the opening in the overhang at the rear of the housing 60.

The dial 87 is then installed to the full depth of the recess 92 with the set screw 90 tightened into place with the indicia upon the dial 87 and indicating arrow 97 oriented for the valve to be in closed position. The spring plug 84 is snapped into place, the electrical connections made as at 117, and the cap 118 is installed with the screw 120. The dial can be installed afterwards to a properly adjusted position with respect to the setting of the thermostat upon the initial test of the iron. Preferably the lowest regulating point of approximately 200 is set with the dial in proper position to indicate the 200 mark if the thermostat has not already been preset before assembly. 7

Having thus described the invention, the operation thereof will be understood. The iron is upended to rest upon the handle and overhang, the plug 84 is removed and water is put into the tank 62 through the sleeve 74, displaced air being vented through the sleeve nut 73. When the fill limit is reached, the plug 84 is snapped back in place, the dial 15 adjusted to the temperature desired, and the cord 17 plugged into the convenience outlet of a house circuit. Thereafter the heater 35 rapidly warms the. heater-carrying member 36 and heat is conducted therefrom through the lands 32 and 33 into the bottcm member 20 until the thermostat 23 breaks contact. Thereafter, or during the warmup period, just before ironing operations begin, the dial 87 can be turned to permit the desired amount of water to drip into the vaporization chamber 39 past the valve port 68. The water entering the vaporization chamber 39 will take heat from the heat bearing member 36 to the extent that it is neded to vaporize, and since this heat is not under the control of the thermostat directly, and does not have to pass through the lower member 20 to vaporize the Water, the heat which will pass through the lower member 20 to be effective in controlling the thermostat is. that whichis left over that is not absorbed by the water. However, in event that the water is converted to steam of high temperature, the steam passing along the channel 34 in the cavity 25 will transfer heat thereto before the steam passes out of the openings 27 onto the garment being pressed, and thus, if the steam is at a temperature higher than the temperature at which the lower member 20 is being controlled, the thermostat will respond thereto, the same as heat conducted in a limited controlled relationship through the lands 32 and 33 to the sole plate,

and. between the two maintain the iron at a substantially low temperature for ironing fabrics at low temperatures without lowering the. effective heat present. for purposes of; vaporization of the water. In fact, if water enters the vaporization chamber without enough heat being present there to vaporize it, it will be present there to absorb the first heat immediately when the thermostat again turns on the heater, and since this heat is absorbed to make steam, constitutes surplus heat supplied by the heater over and above that needed to heat the lower member to the control temperature. Thus there can be no water spotting of garments being ironed, once the iron is brought up to the set ironing temperature.

Consequently, it will be seen from the description of the invention and the discussion of its principle of operation that various and further modifications can be made to accomplish the objects enumerated without departing from the spirit of the invention, the scope of which is commensurate with the appended claims.

What is claimed is:

1. In an electric steam iron a sole plate comprising a heater free bottom plate of high heat conductive metal having a, channel in the top face and openings extending through the stock thereof from the channel to the bottom face, a metal encased heater, a member of high heat conductive metal having the heater embedded. in the stock thereof and having a flange on the bottom thereof received in said channel in limited heat exchange contact with the bottom plate, a thermostat in direct heat exchange relationship solely with the bottom plate but in close proximity to the channel, said member having a compartment in its upper face in close proximity to the heater and an opening through its stock leading from said compartment to said channel, a cover for said compartment made of low heat conductive metal, and valve means carried by said cover for metering water to said compartment.

2. The combination called for in claim 1 in which the surface area of said compartment is greater than said limited heat exchange contact area.

3. The combination called for in claiml in. which said channel is located between said heater and said bottom plate.

4. The combination called for in claim 1 in which limited heat exchange contact is equivalent to the heat exchange contact of a continuously operating watt heater embedded in high heat conductive metal.

5. The combination called for in claim 1 in which the effective contact area of said limited heat exchange contact is less than one-half of the effective area of heat transfer between the heater and said member in which it is embedded.

6. The combination called for in claim 1, in which the effective contact area of heat transfer between said plate and member is less than the area of contact between. the vaporized fluid and said member.

7. In an electric steam iron a tank for receiving water and a sole plate below said tank comprising a heater free bottom plate of high heat conductive metal of substantially uniform thickness over the major portion there of and having flanges defining a cavity in the top face with openings extending through the stock thereof from the cavity to the bottom face, a resistance heater encased in a metal sheath, a member of high heat conductive metal having the heater embedded in the stock there. of and having lands on the bottom thereof received in said cavity in limited heat exchange contact with the bottom plate, a thermostat in direct heat exchanging relationship solely with the bottom plate in close proximity to the cavity, said member having a compartment in its upper face in close proximity to the heater and an opening through its stock leading from said compartment to said channel, a cover for said compartment made of low heat conductive metal, and valve means carried" by said cover for metering water to. said compartment.

8. The combination called for. in claim 7 inwhich said compartment. includes fluid paths which. separate, and

rejoin determined by walls in intimate heat exchange relationship with said heater.

9. In a steam pressing iron, an electrically heated sole plate comprising a fabric contacting member having high thermal conductivity, a heater carrying member, means for effecting limited heat exchange between the first member and the second member, said second member having a steam generating cavity therein, a cover plate of low heat conductive material covering said cavity to define a steam generating chamber and apertured above said cavity with a threaded opening, said chamber being in close proximity to said heater, a water tank vented to the atmosphere and located above and spaced from the second mentioned member and having a downwardly offset apertured portion in alignment with the aperture in the cover plate, a sleeve nut engaging said tank and threaded in said threaded opening to hold said tank and cover plate rigidly in position, valve means in said sleeve nut for controlling the flow of water from the tank to the cavity, and thermostat means engaging said fabric contacting member for controlling said heater.

10. In an electric steam iron, a sole plate comprising a bottom plate of high heat conductivity defining a channel in the top face and openings from the channel to the bottom face thereof, a heater, a member of high heat conductivity, said heater being embedded in said member, means for effecting a predetermined and limited heat exchange between said member and said plate, said member having a compartment in its upper face in good heat exchange relationship with said heater and defining an opening from said compartment to said channel and valve means metering water to said compartment.

11. In an electric steam iron, a sole plate comprising a bottom plate of high heat conductivity defining a channel in the top face and openings from the channel to the bottom face thereof, a heater, a member of high heat conductivity, said heater being embedded in said member, means for effecting a predetermined and limited heat exchange between said member and said plate, a thermostat in direct heat exchange relationship solely with the bottom plate, said member having a compartment in its upper face in good heat exchange relationship with said heater and defining an opening from said compartment to said channel and valve means metering water to said compartment.

12. The combination called for in claim 9 wherein said sole plate defines a channel in the top face and 10 openings extending through the plate from the channel to the bottom face thereof, said thermostat means being in direct heat exchange relationship solely with said bottom plate but in close proximity to said channel.

13. The method of ironing and revitalizing fabrics comprising subjecting fabric to heat and pressure over a pressing area at a temperature as low as the boiling point of water and simultaneously therewith flash vaporizing drops of mixed water and a mineral oil the vaporization point of which is considerably above that of water to generate a vapor of steam and oil at a temperature above the vaporization point of the mineral oil, and supplying said vapor to said fabric within said pressing area.

14. The method of ironing fabrics comprising flash generating drop by drop from a mixture of water and an oil whose vaporization point is considerably above the boiling point of water a vapor with heat derived from a common heat source at a temperature above the vaporization point of the oil and supplying said vapor to a fabric within a pressing area, and subjecting the fabric within said pressing area to pressure and heat at a predetermined uniform pressing temperature lower than the temperature of said vapor derived through limited conductivity of heat from said common heat source and substantially independent of the temperature of said vapor.

15. The method of ironing fabrics comprising sub jecting fabric to heat under ironing pressures over a pressing area at a pressing temperature as low as approximately 200 F. and simultaneously therewith flash vaporizing drop by drop a mixture of water and an oil whose vaporization point is considerably above the boiling point of the water to form a vapor at a temperature above the'vaporization point of the oil and supplying said vapor to said fabric within said pressing area at a temperature above said pressing temperature to revitalize the fabric.

References Cited in the file of this patent UNITED STATES PATENTS Re. 21,632 Jones Nov. 26, 1940 1,863,284 Rollman June 14, 1932 2,222,305 Tricomi et al Nov. 19, 1940 2,384,839 Kistner Sept. 18, 1945 2,515,100 Sutton July 11, 1950 2,606,377 Edwards Aug. 12, 1952 

